Having determined that the initial reaction sequence in exercise-induced asthma has to do with respiratory heat exchange and airway cooling, during the coming year we plan to initiate studies designed to examine the other aspects of the reaction. We plan to determine if airway cooling activates mast cells as cooling of the skin does in cold urticaria, and specifically, we will examine systemic arterial blood before, during and after exercise and eucapnic hyperventilation to determine if we can observe release kinetics of histamine and of neutrophile chemotactic factor of anaphylaxis.